Center for Biofilm Engineering

Abstract:  

"Experimental Osteomyelitis Treatment with 
Antibiotic-Impregnated Hydroxyapatite" 

02-031   A calcium hydroxyapatite antibiotic implant was evaluated to determine its efficacy as an antibiotic delivery system in a localized osteomyelitis rabbit model. Localized rabbit tibial osteomyelitis was developed with an intramedullary injection of methicillin resistant Staphylococcus aureus. Infected rabbits were randomized and divided into eight groups 
depending on treatment with or without debridement, systemic antibiotics,  antibiotic-impregnated polymethylmethacrylate beads, or calcium hydroxyapatite 
implants with and without antibiotic impregnation. All treatments began 2 weeks after infection. After 4 weeks of therapy, the involved bones were cultured for concentrations of  Staphylococcus aureus per gram of bone. Rabbits (n = 11) that had calcium hydroxyapatite 
(impregnated with vancomycin) implanted into the dead space after the debridement surgery had an 81.8% infection clearance after treatment. Rabbits (n = 10) that had polymethylmethacrylate beads (impregnated with vancomycin) implanted into the dead space after debridement surgery had a 70% clearance rate. All other treatment modalities resulted in less than 50% clearance rates. Calcium hydroxyapatite may be an effective alternative to polymethylmethacrylate for providing local antibiotic therapy in cases of methicillin 
resistant Staphylococcus aureus osteomyelitis.

Shirtliff M.E., J.H. Calhoun, and J.T. Mader, "Experimental Osteomyelitis Treatment with 
Antibiotic-Impregnated Hydroxyapatite," Clin. Orth. Related Res., 401:239-247 (2002).